This invention relates to a three-dimensional image processing apparatus and an external memory device to be used therewith. More particularly, the invention relates to a three-dimensional image processing apparatus which displays on a display device an image of a player controlled object or other objects, existing in three-dimensional space, from the perspective of a predetermined xe2x80x9ccameraxe2x80x9d position (the point of view). BACKGROUND AND SUMMARY OF THE INVENTION
The conventional so-called 3D (3-Dimensional) video game uses player controlled or operable objects (objects operable by an operator) configured with three-dimensional data when viewed by an apparent camera at predetermined angles and distances, thereby obtaining displayed images. In the conventional game, however, if a background image (e.g., a wall) or an object used as an opponent character (another object) comes between the player controlled object and the xe2x80x9ccameraxe2x80x9d, or if another object is moved to interrupt the line of sight between the operable object and the camera, the operable object can not be viewed in the three-dimensional world. To this end, there has been a limitation in the conventional 3D games in that the other object has to be arranged by a program not to exist between the operable object and the camera.
It is therefore an object of the present invention to provide an image processing apparatus which is capable of displaying an operable object at substantially all times and hence free from limitation in arranging other objects.
The illustrative image processing apparatus displays on a display an operable object image and another object existing in a three-dimensional space from a predetermined viewing or xe2x80x9cphotographicxe2x80x9d position. The image processing apparatus includes an external memory which stores operable object and the other object data and a predetermined program. The system uses an input controller which inputs data which alters the position of the operable object in the three-dimensional space. Operable object position data generating hardware and software generates operable object position data so as to alter the position of the operable object in the three-dimensional space based on the data input by the input controller. The three-dimensional data is created based on the data stored in the external memory and the operable object position data. Point of view position data is generated representing photographing position data in the three-dimensional space for displaying the operable object. The system detects whether or not the other object exists between the xe2x80x9ccameraxe2x80x9d view position and the operable object position. If so, the system alters the photographing position data such that the other object is not existent between the photographing position and the operable object position when the detecting means detects existence of the other object. The system creates display data for displaying the image of the operable object photographed from a predetermined position in the three-dimensional space based on the three-dimensional data and the photographing position data; and image signal generating circuitry outputs an image signal to the display based on the generated display data.
The system determines whether or not there is a possibility of a collision between the operable object and a polygon plane of the other object. If there is a possibility of a collision of the operable object with the other object, the camera position is changed so that the other object does not exist between the operable object and the camera. Therefore, the operable object is xe2x80x9cphotographedxe2x80x9d without interference by the other object.
In accordance with the present invention, even if another object is permitted to freely move, it is possible to display at substantially all times an operable object on a screen of a display. Consequently, if the present invention is applied to a game apparatus, the operable object can be displayed at all times on a display, even for a game that involves an operable object and a number of other objects moving around on the display screen.